TABLE 1

Accuracy Studies of SPECT

Study	Reference standard	SPECT criteria	Ventilation agent	SPECT sensitivity	SPECT specificity	SPECT PPV	Prospective	Patient characteristic
Corbus (4)	Conventional angio	Revised PIOPED: high or inter = PE; low or normal = no PE	^99mTc-DTPA	Not done	Not done	18/29 (62%)	No	Consecutive suspected PE
Bajc (30)	CT angio	≥2 mismatches = PE; 1 mismatch = no PE	Technegas	24/26 (92%)	54/76 (71%)		No	Consecutive suspected PE
Bajc (30)	Consensus, SPECT, CT angio	≥2 mismatches = PE; 1 mismatch = no PE	Technegas	601/608 (99%)	1,153/1,177 (98%)		No	Consecutive suspected PE
Palla (2)	Conventional angio if planar V/Q perfusion defects	Defects in ≥ 1 segment	¹³³Xe	56/62 (90%)	75/118 (64%)		Yes	All referred for suspected PE, not consecutive
Collart (20)	Consensus V/Q, sonography, CT angio, D-dimer	Wedge-shaped defect	Not done	12/15 (80%)	49/51 (96%)		Yes	Consecutive suspected PE in emergency department
Reinartz (22)	Not stated	≥1 mismatch	Technegas	Reader 1, 96%	Reader 1, 96%		No	Consecutive suspected PE
				Reader 2, 93%	Reader 2, 100%
				Reader 3, 89%	Reader 3, 100%
Reinartz (23)	Consensus, including SPECT and CT angio	≥1 mismatch	Technegas	36/37 (97%)	42/46 (91%)		No	Suspected PE
Bajc (19)	Consensus, including SPECT and CT angio	≥2 seg or subseg mismatches = PE; 0 mismatch = no PE	^99mTc-DTPA	Reader A, 13/13 (100%)	Reader A, 37/40 (93%)		Yes	51 suspected PE
				Reader B, 13/13 (100%)	Reader B, 37/39 (95%)			2 treated PE
Hata (32)	CT angio if high or inter SPECT	Seg perfusion defect, 2 or 3 planes	Not done	Not done	Not done	4/8 (50%)	Yes	Screening after cancer surgery
Lemb (31)	SPECT better, new defects, or normalized = PE; SPECT unchanged = no PE	≥1 mismatch = PE; 0 mismatch = no PE	Technegas	44/46 (96%)	38/39 (97%)		No	All referred for suspected PE

PPV = positive predictive value; angio = angiography; inter = intermediate; seg = segmental; subseg = subsegmental.